This invention relates to an improvement of hopper means for use in water channel forming machine for laying a paving material prepared, for example, by mixing asphalt and sand to construct a water channel continuously.
The water channel forming machine of the kind specified includes hopper means having screws mounted on the bottom thereof, and is arranged to send out continuously the paving material accommodated in the hopper means by the action of the screws. However, such conventional water channel forming machine is disadvantageous in that the high viscosity of the paving material causes formation of cavities in vicinity of the screws which sometimes renders sending-out of the paving material by the screws impossible.